Add language filter to the admin/content/site-settings views

Makes sense, thanks for the suggestion. Testing shows up when I activate language & create a second language. No filter shows when multilingual not enabled. Seems fine. Okay for you?

(other changes come because config installs don't get updated with update hooks, tons of outdated ones in core for example - fine to ignore those in review)

Works fine for me, thanks!

Automatically closed - issue fixed for 2 weeks with no activity.